samples: fix create large object example (#431)

Author: matt-catalyst

samples/ObjectStore/v1/objects/create_large_object.php

@@ -17,7 +17,7 @@
 $service = $openstack->objectStoreV1();
 $container = $service->getContainer('{containerName}');
 
-$object = $container->createObject([
+$object = $container->createLargeObject([
     'name'             => '{objectName}',
     'stream'           => new \GuzzleHttp\Psr7\Stream(fopen('/path/to/large_object.mov', 'r')),